TP-7 raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-01-01. Anything still debated is marked as such rather than presented as settled.
The compound has a calculated molecular weight near 751.9 daltons and carries a net positive charge at physiological pH because of its arginine residue. It dissolves freely in water and in common aqueous buffers, and typically appears as a white or off-white lyophilized powder. The amide backbone makes the molecule susceptible to peptidases, which limits oral use and favors intranasal or parenteral routes. Nomenclature in the literature varies: the substance is also described by the sequence abbreviation TP-7 and by a Russian trade designation.
Regulatory status differs sharply by region. Selank holds a Russian marketing authorization, where it is supplied mainly as nasal drops, while authorities elsewhere have not approved it for medical use. Material sold internationally is therefore usually labeled as a research chemical rather than a medicine. Peer-reviewed publications come predominantly from Russian laboratories, and sample sizes are generally small. Whether the compound produces comparable effects under independent, well-controlled replication remains an open question that the broader literature has not settled.
Selank is a synthetic heptapeptide developed in Russia as a structural analogue of tuftsin, a naturally occurring immunomodulatory tetrapeptide. Its sequence, Thr-Lys-Pro-Arg-Pro-Gly-Pro, keeps the tuftsin core at the N-terminus and appends a Pro-Gly-Pro tail. Researchers at the Institute of Molecular Genetics in Moscow synthesized the compound during the 1990s while searching for peptides with combined anxiolytic and immunomodulatory activity. The added tail was intended to resist enzymatic cleavage and prolong the molecule's presence in circulation.
Reversed-phase high-performance liquid chromatography is the standard technique for estimating peptide purity. The result is a peak-area percentage, which describes how much of the detected material elutes as the main peak in one run. Mass spectrometry confirms the molecular mass and can reveal truncated, adducted, or otherwise modified species. Amino acid analysis or tandem mass spectrometry can address sequence fidelity when identity is in doubt. None of these measurements, taken alone, establishes that a sample is fit for any specific purpose.
Lyophilized selank is normally supplied as a dry powder and is considered stable for extended periods when kept cold and dry. Moisture uptake is the main practical threat, because absorbed water promotes both hydrolysis and aggregation in the solid state. Vials are usually warmed to room temperature before opening so that condensation does not form on the powder. Supplier documentation commonly specifies -20 °C for routine storage, with -80 °C used for material intended to be archived for years.
Once dissolved, the peptide is markedly less stable than the dry powder. Aqueous solutions are subject to backbone hydrolysis and to microbial growth when they are handled without sterile technique. Buffered solutions near neutral pH are common for short-term laboratory work, while acidic conditions are sometimes used to improve solubility. Analytical laboratories generally prepare working solutions fresh rather than storing them, and a residual water film left in a reopened vial can seed degradation even when the container appears dry.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Analog of the tetrapeptide tuftsin |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Reported consistently across pharmacopoeial descriptions |
| Appearance | White to off-white lyophilized powder | Typical form of research-grade material |
| Solubility | Freely soluble in water | Aqueous buffers; poor in nonpolar solvents |
| Typical storage temperature | -20 degrees Celsius | Lyophilized powder; protect from moisture |
Development took place at the Institute of Molecular Genetics of the Russian Academy of Sciences, where a series of short peptides were designed in the 1980s and 1990s. Selank was selected from variants of tuftsin that showed resistance to plasma peptidases. Russian regulatory approval covers it as an anxiolytic agent given intranasally. Outside that market the compound is normally handled as a research chemical rather than a medicine, and no widely recognised international pharmacopoeial monograph exists. The name Selank is a coined trade designation rather than a systematic chemical name.
Enzymatic stability motivates the extra three residues at the carboxyl end. Native tuftsin is cleaved quickly by circulating aminopeptidases and carboxypeptidases, which limits its duration of action and its usefulness as a tool compound. Extending the chain with proline-rich segments is a common design tactic because proline constrains the backbone and slows proteolysis. The same Pro-Gly-Pro motif appears in other Russian-developed peptides of the era. Whether the full seven-residue chain is required for activity, or whether it acts mainly as a prodrug releasing tuftsin, remains unresolved.
Quantification in biological matrices relies on liquid chromatography coupled to tandem mass spectrometry with stable-isotope internal standards. Low plasma concentrations and adsorption to container surfaces both complicate measurement. Solid-phase extraction is often needed to reduce matrix interference before injection. Reported limits of quantification differ widely between laboratories, which makes direct comparison of pharmacokinetic results difficult and limits meta-analysis.
Peptide bonds are vulnerable to protease attack, and Selank is no exception. Measured half-life in serum is short, on the order of minutes in several reports, which explains why intranasal administration is the common route described in the literature. Absorption across the nasal mucosa partially bypasses first-pass hepatic metabolism. Quantitative data on human bioavailability remain limited and are difficult to compare across studies.
Animal studies have examined behaviour in tests of anxiety, memory retention and stress response, and several report changes in neurotrophic or neurotransmitter-related markers. The human evidence base is much smaller, consisting mainly of short trials conducted in Russia with limited reporting in English-language journals. Sample sizes are modest and outcome measures vary between studies, so the findings are best described as preliminary. Independent replication under modern trial standards has not been widely reported.
Outside its country of origin the compound is generally handled as a research chemical rather than an approved medicine. No regulatory approval from the United States Food and Drug Administration or the European Medicines Agency has been granted for human use. Identity and purity are normally checked by reverse-phase high-performance liquid chromatography, with mass spectrometry used to confirm the molecular mass. Lyophilised material is stored cold and desiccated, and repeated freeze-thaw cycles are avoided.
Published work on this peptide almost always uses intranasal delivery, with drops or a spray applied to the nasal mucosa. Some animal experiments have used subcutaneous or intraperitoneal injection, and a smaller number have compared routes directly. Oral administration is not a focus of the literature, because short peptides of this size are broken down by digestive enzymes and cross intestinal barriers poorly. How much of an intranasal dose reaches the bloodstream intact in humans remains an open question.
If the player rescues all of the Little Sisters, Jack takes them back to the surface with him and adopts five as his daughters. Tenenbaum happily narrates how they go on to live full lives under his care, eventually surrounding him on his deathbed. If the player harvests any of the Little Sisters, Jack turns on the Little Sisters to harvest their ADAM. Tenenbaum condemns Jack as he leads a group of Splicers to take over a nuclear warhead-armed submarine. Depending on how many of the Little Sisters are harvested, Tenenbaum's narrative changes from sad and mournful to angry and harsh.
Psychological assessment usually includes determining a mental disorder diagnosis. Many countries use the International Statistical Classification of Diseases and Related Health Problems (ICD-10 or ICD-11) while the US most often uses the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). Both are nosological systems that largely assume categorical disorders diagnosed through the application of sets of criteria including symptoms and signs. Several new models are being discussed, including a "dimensional model" based on empirically validated models of human differences (such as the five factor model of personality) and a "psychosocial model", which would take changing, intersubjective states into greater account. The proponents of these models claim that they would offer greater diagnostic flexibility and clinical utility without depending on the medical concept of illness. However, they also admit that these models are not yet robust enough to gain widespread use, and should continue to be developed.
== Applications == Pyrolysis is most commonly used in the treatment of organic materials. It is one of the processes involved in the charring of wood. In general, pyrolysis of organic substances produces volatile products and leaves char, a carbon-rich solid residue. Extreme pyrolysis, which leaves mostly carbon as the residue, is called carbonization. Pyrolysis is considered one of the steps in the processes of gasification or combustion. Compared to syngas, pyrolysis gas has a high percentage of heavy tar fractions, which condense at relatively high temperatures, preventing its direct use in gas burners and internal combustion engines. The process is used heavily in the chemical industry, for example, to produce ethylene, many forms of carbon, and other chemicals from petroleum, coal, and even wood, or to produce coke from coal. It is used also in the conversion of natural gas (primarily methane) into hydrogen gas and solid carbon char, recently introduced on an industrial scale. Aspirational applications of pyrolysis would convert biomass into syngas and biochar, waste plastics back into usable oil, or waste into safely disposable substances.
Selective norepinephrine reuptake inhibitors (sNRIs) are a class of drugs that have been marketed as antidepressants and are used for various mental disorders, mainly depression and attention deficit hyperactivity disorder (ADHD). The norepinephrine transporter (NET) serves as the fundamental mechanism for the inactivation of noradrenergic signaling because of the NET termination in the reuptake of norepinephrine (NE). The selectivity and mechanism of action for the NRI drugs remain mostly unresolved and, to date, only a limited number of NRI-selective inhibitors are available. The first commercially available selective NRI was the drug viloxazine (Qelbree), developed as an antidepressant but later marketed as a treatment for ADHD. Reboxetine (Edronax) was developed as a first-line therapy for major depressive disorder. Atomoxetine (Strattera) is another potent and selective NRI which is also effective and well-tolerated for the treatment of ADHD in adults, particularly for those patients at risk of substance abuse.
=== Accommodations === Along with obesity came the accommodations made of American products. Child-safety seats in 2006 became modified for the 250,000 obese U.S. children ages six and below. The obese incur extra costs for themselves and airlines when flying. Weight is a major component to the formula that goes into the planes take off and for it to successfully fly to the desired destination. Due to the weight limits taken in consideration for flight in 2000, airlines spent $275 million on 350 million additional gallons of fuel for compensation of additional weight to travel. Accommodations have also been made in work place environments for workers, including those such as chairs with no armrests and access to work outside of the office. Occupational safety may require accommodations such as wider, more robust office chairs that allow for safe and comfortable working.
Sources: en.wikipedia.org
Hummingbirds resemble sunbirds. The former live in the Americas and belong to an order or superorder including the swifts, while the latter live in Africa and Asia and are a family in the order Passeriformes. Also the nectar-feeding Hawaiian honeycreepers resemble the two and differs from other honeycreeper. Flightlessness has evolved in many different birds independently. However, taking this to a greater extreme, the terror birds, Gastornithiformes and dromornithids (ironically all extinct) all evolved the similar body shape (flightlessness, long legs, long necks, big heads), yet none of them were closely related. They also share the trait of being giant, flightless birds with vestigial wings, long legs, and long necks with the ratites, although they are not related. Certain longclaws (Macronyx) and meadowlarks (Sturnella) have essentially the same striking plumage pattern. The former inhabit Africa and the latter the Americas, and they belong to different lineages of Passerida. While they are ecologically quite similar, no satisfying explanation exists for the convergent plumage; it is best explained by sheer chance. Resemblances between swifts and swallows is due to convergent evolution. The chimney swift was originally identified as chimney swallow (Hirundo pelagica) by Carl Linnaeus in 1758, before being moved to the swift genus Chaetura by James Francis Stephens in 1825.
More recently gene therapy has been attempted as an alternative to the bone marrow transplant. Transduction of the missing gene to hematopoietic stem cells using viral vectors is being tested in ADA SCID and X-linked SCID. In 1990, four-year-old Ashanthi DeSilva became the first patient to undergo successful gene therapy. Researchers collected samples of DeSilva's blood, isolated some of her white blood cells, and used a retrovirus to insert a healthy adenosine deaminase (ADA) gene into them. These cells were then injected back into her body, and began to express a normal enzyme. This, augmented by weekly injections of ADA, corrected her deficiency. However, the concurrent treatment of ADA injections may impair the success of gene therapy, since transduced cells will have no selective advantage to proliferate if untransduced cells can survive in the presence of the injected ADA.
Although WHO recommends artemisinin-based remedies for treating uncomplicated malaria, resistance to the drug can no longer be ignored. Also in the 1970s Chinese researcher Zhang TingDong and colleagues investigated the potential use of the traditionally used substance arsenic trioxide to treat acute promyelocytic leukemia (APL). Building on his work, research both in China and the West eventually led to the development of the drug Trisenox, which was approved for leukemia treatment by the FDA in 2000. Huperzine A, an extract from the herb, Huperzia serrata, is under preliminary research as a possible therapeutic for Alzheimer's disease, but poor methodological quality of the research restricts conclusions about its effectiveness. Ephedrine in its natural form, known as má huáng (麻黄) in TCM, has been documented in China since the Han dynasty (206 BCE – 220 CE) as an antiasthmatic and stimulant. In 1885, the chemical synthesis of ephedrine was first accomplished by Japanese organic chemist Nagai Nagayoshi based on his research on Japanese and Chinese traditional herbal medicines Pien tze huang was first documented in the Ming dynasty.
=== Mice === Mouse FPR receptors localize to chromosome 17A3.2 in the following order: Fpr1, Fpr-rs2 (or fpr2), Fpr-rs1 (or LXA4R), Fpr-rs4, Fpr-rs7, Fpr-rs7, Fpr-rs6, and Fpr-rs3; Pseudogenes ψFpr-rs2 and ψFpr-rs3 (or ψFpr-rs5) lie just after Fpr-rs2 and Fpr-rs1, respectively. All of the active mouse FPR receptors have ≥50% amino acid sequence identity with each other as well as with the three human FPR receptors. Based on its predominantly intracellular distribution, mFpr-rs1 correlates, and therefore may share functionality, with human FPR3; However, the large number of mouse compared to human FPR receptors makes it difficult to extrapolate human FPR functions based on genetic (e.g. gene knockout or forced overexpression) or other experimental manipulations of the FPR receptors in mice.
Sources: en.wikipedia.org
The "Cave of the Sixteen sword bearers" ("Höhle der Schwertträger", 十六带剑者窟) is a famous cave with a series of murals showing swordsmen wearing caftans and armed with long sword and daggers. These murals have been carbon dated to 432–538 CE. The swordsmen have also been dubbed the "Tocharian donors". The interpretations of the nationality or ethnicity of the donors have varied. Some authors claim that the donors are indeed Tocharians, an elusive people of the Tarim Basin who spoke the well-documented Tocharian language, the easternmost Indo-European language. According to this thesis, the donors in the murals are of the Indo-European type, wearing Iranian-style clothes and reddish hair. A more recent interpretation is that the sword-bearers are actually Hephthalites, who are known to have occupied the Tarim Basin from 490 to 560 CE, precisely at the time the paintings were made. Kucha was specifically part of their dominion between 502 and 556 CE. The clothing style, the iconography and the physiognomy of the donors are said to be extremely close to those depicted in the paintings of Tokharistan (Bactria), the center of Hephthalite power, at sites such as Balalyk tepe or Dilberjin Tepe. In particular, the coat with single folded lapel is considered as a result of Hephthalite influence, whereas traditional Kuchean coats had two lapels. At present, the most prevalent opinion among academics seems to be that the Hephthalites were initially of Turkic origin. Similar donors can be seen in the Kumtura Caves.
Other studies say it has been found at low frequency in samples of Han Chinese, and Q-M120 is also found among other East Asians and Southeast Asians like Hmong Daw in Laos, Japanese, Dörwöd Kalmyks, Koreans, Mongols, Tibetans, Uygurs, and Vietnamese. It also has been found among Bhutanese, Murut people in Brunei, Tuvans, Nivkhs, Koryaks, Yukaghirs. Sub-lineages of haplogroups C2b, O2a2a and O1b-M268 are common for populations from Eastern China. In particular, many individuals from Eastern China have haplogroups related to O1b1a2. This haplogroup is quite rare in East Asia but is mostly found in the southeastern part of Northeastern China and part of Southeast Asia, especially among Han Chinese individuals.
Although neptunium halide compounds have not been nearly as well studied as its oxides, a fairly large number have been successfully characterized. Of these, neptunium fluorides have been the most extensively researched, largely because of their potential use in separating the element from nuclear waste products. Four binary neptunium fluoride compounds, NpF3, NpF4, NpF5, and NpF6, have been reported. The first two are fairly stable and were first prepared in 1947 through the following reactions:
Sources: en.wikipedia.org
Selank is a synthetic seven-amino-acid peptide modeled on tuftsin, a fragment of the immunoglobulin G heavy chain. It was designed in Russia to combine anxiolytic and immunomodulatory properties in one molecule.
The first four residues of Selank reproduce the tuftsin sequence Thr-Lys-Pro-Arg. A Pro-Gly-Pro extension at the C-terminus was added to slow enzymatic breakdown and extend residence time.
It holds marketing authorization in Russia, where nasal drop formulations are sold. No equivalent approval exists in the European Union, the United States, or most other countries.
Sealed, desiccated storage at -20 °C or colder is the standard recommendation for research-grade material. Vials should reach room temperature before they are opened, which limits condensation. Repeated temperature cycling is discouraged.